Detection of Zinc in the Very Metal-Poor Post-AGB Star HR 4049
نویسندگان
چکیده
منابع مشابه
CS 30322 - 023 : an ultra metal - poor TP - AGB star ? ⋆
Context. The remarkable properties of CS 30322-023 became apparent during the course of a high-resolution spectroscopic study of a sample of 23 carbon-enhanced, metal-poor (CEMP) stars. Aims. This sample is studied in order to gain a better understanding of sand r-process nucleosynthesis at low metallicity, and to investigate the role of duplicity. Methods. High-resolution UVES spectra have bee...
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The C I, Na I D, and Hα lines of the postAGB binary HR 4049 have been studied. Na I D variability results from a photospheric absorption component ([Na/H]=−1.6 ± 0.2) which follows the velocity of the primary and a stationary, non-photospheric component. An emission component is attributed to the circumbinary disc, and an absorption component to mass-loss from the system with a velocity of 5.3±...
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ژورنال
عنوان ژورنال: Publications of the Astronomical Society of Japan
سال: 2002
ISSN: 0004-6264,2053-051X
DOI: 10.1093/pasj/54.5.765